1. Field of the Invention
This invention relates to a novel 2-alkoxy- or acyloxy-2-aryl-1,3-propanediol or dioxane derivative from which a 2-aryl-1,3-propanediol, a precursor or intermediate for synthesizing physiologically active substances such as felbamate of the formula (A): ##STR3## that acts as an antiepileptic, can be derived in a high yield, and a process for producing the same. The present invention also relates to a process for producing a 2-aryl-1,3-propanediol obtained from that derivative, and a process for producing a glycol monoether that can serve as a starting material for synthesizing the derivative.
2. Description of the Related Art
Hitherto, 2-aryl-1,3-propanediols are produced by a process in which an aryl-substituted malonate is reduced, a process in which a 2-nitro-2-aryl-1,3-propanediol is subjected to catalytic hydrogenation, or a process in which an ester of 1-hydroxymethyl-1-phenyl acetic acid is reduced.
As the above process for producing 2-aryl-1,3-propanediols by reduing malonates, specifically a process in which an expensive metal hydride reducing agent such as lithium aluminum hydride is used in a stoichiometric amount [U.S. Pat. Nos. 5,091,595 and 4,982,016 and J. Org. Chem., 54, 1198 (1989)] and a process in which hydrogenation is carried out in the presence of copper chromite catalyst under application of a pressure of as high as 5,000 p.s.i. [J. Am. Chem. Soc., 70, 3121 (1948)] are known in the art.
These processes, however, have economical and operational difficulties from the viewpoint of their application in an industrial scale, and have room for greater improvements.
The process in which a 2-nitro-2-aryl-1,3-propanediol is subjected to catalytic hydrogenation (U.S. Pat. Nos. 5,072,056 and 4,868,327) has the problem that nitroalkane derivatives full of danger of explosion must be handled.
The process in which an ester of 1-hydroxymethyl-1-phenyl acetic acid is reduced (U.S. Pat. No. 5,239,121) also has the problems that the ester of 1-hydroxymethyl-1-phenyl acetic acid itself may readily undergo dehydration to form an active acrylic acid derivative and that expensive metal hydride reducing agents must be used.